Article: How to diagnose suspension problems An article written by Jerry Hastings for www.Helium.com
Continued from previous blog...
Rear axles on rear driven vehicles sort of fall into the category of suspensions but their role is unique in the scheme of things. Rear axles on front wheel drive vehicles can be considered suspension components but they also provide the link between wheel bearings, hubs and wheels.
When you really want to define the term "suspension", axles of all sorts really do not fit but are in a class by themselves and generally shops and literature recognizes them that way.
Items like tie rods and tie rod ends, idler arms, pitman arms, control arms and other components all the way up to the steering wheel, fall under the classification of steering components exclusively and should not be confused with suspension components.
Slack in these steering components can best be found by leaving the vehicle weight on the wheels and observing each component while a helper turns the steering wheel slowly back and forth only the amount necessary to cause some movement. Normally slack in steering components can be felt as slack at the steering wheel. If that is the case, turning the steering wheel back an forth only as far as the amount slack present will help locate the source of that slack.
Ball joints and kingpins usually wear to some extent especially if the wrong type of grease is used or the frequency of grease jobs are not adequate enough. Slack results from this wear. A normal cheap real grease is better than a high dollar synthetic grease for these and all suspension and steering components. The only place synthetic grease should be used is in the wheel bearings. I know, the advertisements says this or that but advertisements are sometimes far from reality.
Two people are required for a lot of suspension diagnosis techniques, especially in the absence of specialized equipment. Most of the following require two people. One to provide movement of the part in question and the other to watch the part for any signs of slack.
Upper ball joints are the easier of the two to check for slack. Simply jack the weight off the wheels while a friend observes the movement in the ball joints (other than pivoting movement). Lower ball joints may require a pry bar placed under the wheel while the vehicle is jacked up, and prying upward while observing the lower ball joint for the same type of movement. Continued.....
